Six fungal metabolites, of which five were new, including one (1) with a dioxa[4.3.3]propellane ring system, were discovered, identified, and structurally elucidated from Neosetophoma sp. (strain MSX50044); these compounds are similar to the bis-tropolone, eupenifeldin. Three of the meroterpenoids are potent cytotoxic agents against breast, ovarian, mesothelioma, and lung cancer cells with nanomolar IC50 values while not inducing mitochondrial toxicity at 12.5 μM.

Four new cyclopenta­[b]­benzofuran derivatives based on an unprecedented carbon skeleton (1–4), with a dihydrofuran ring fused to dioxanyl and aryl rings, along with a new structural analogue (5) of 5‴-episilvestrol (episilvestrol, 7), were isolated from an aqueous extract of a large-scale re-collection of the roots of Aglaia perviridis collected in Vietnam. Compound 5 demonstrated mutarotation in solution due to the presence of a hydroxy group at C-2‴, leading to the isolation of a racemic mixture, despite being purified on a chiral-phase HPLC column. Silvestrol (6) and episilvestrol (7) were isolated from the most potently cytotoxic chloroform subfraction of the roots. All new structures were elucidated using 1D and 2D NMR, HRESIMS, IR, UV, and ECD spectroscopic data. Of the five newly isolated compounds, only compound 5 exhibited cytotoxic activity against a human colon cancer (HT-29) and human prostate cancer cell line (PC-3), with IC50 values of 2.3 μM in both cases. The isolated compounds (1–5) double the number of dioxanyl ring-containing rocaglate analogues reported to date from Aglaia species and present additional information on the structural requirements for cancer cell line cytotoxicity within this compound class.

Precursor-directed biosynthesis was used to generate a series of fluorinated verticillins. The biosynthesis of these epipolythiodioxopiperazine alkaloids was monitored in situ via the droplet liquid microjunction surface sampling probe (droplet probe), and a suite of NMR and mass spectrometry data were used for their characterization. All analogues demonstrated nanomolar IC 50 values vs a panel of cancer cell lines. This approach yielded new compounds that would be difficult to generate via synthesis.

During our ongoing research on fungal strains from unexplored sources, the reinvestigation of the CHCl 3 −MeOH extract of the marine-facultative Aspergillus sp. MEXU 27854 yielded a new Nmethyl cyclic pentapeptide (1) along with known butyrolactone II and PF1233 A. In addition, from the marine-facultative Gymnoascus hyalinosporus MEXU 29901, a new alternariol glucoside, 10-O-[β-D-(4-methoxyl-glucopyranosyl)]-4-O-methylalternariol (2) and known alternariol 4-Omethyl ether, alternariol and beauvericin, were isolated. The structures of 1 and 2 were established by detailed spectroscopic data, and their absolute configuration was ascertained by Marfey's analysis and HRESIMS-MS/MS data for 1, and by chemical degradation and optical rotation analysis for 2.

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